Electrical measuring instrument



March 30,1926. 1,578,501

' L. DORFMAN ELECTRICAL MEASURING INSTRUMENT Filed Dec. '7, 1920 wrmssszs: INVENTOR J 5 v g0 Barf/r7071 I Patented Mar. .30

1 .Ummms VLEVO DORFMAN, or, WILKINSBURG, PENNSYLVANIA, assrenoa TQ wnsrinononsn ELECTRIC & MANUFACTURING COMPANY, A oo'nrona'rron or rnnnsrnvama.

ELECTRICAL yrEAsti'RmG' rnsrnumnn'r.

Application filed liecember 7, 1920. Serial No. 428,877

To all w/wm'z'tmay concern: Be it known that LLEo Dorm/L N, a citizen of the United States, an'da resident of Wilkinsburg, in the county of Alleghenyand State of Pennsylvania, have invented a new and useful Improvement in Electrical Measuring Instruments, of which the following is a specification. L My invention relates toel'ectrical measuring instruments andit has special relation to volt-ampere-hour meters. 7 One object of my invention is toprovide an instrument of the above-indicated character which shall be simple and economical to constructandefii'cient and reliable in operation. v

. Another object of my invention is to provide a meter which, under ordinary operation and connection, is adapted to register watt hours, with inductive means whereby the meter will register volt-ampere hours.

The present invention contemplates connectingthe potential winding of an ordinary induction-type watt-hour meter to the circuit, the volt amperes of which are to be measured, and interposlng, between the current winding thereofand the circuit, an in duction regulator which is adapted to be circuits and apparatus embodying my in-,

. 2 is of the usual construction of a watt-hour deflected in accordance with the current in the circuit so that the current which traverses the current winding of said meter shall be proportional to the current traversing the circuit and shall have a predetermined phase relationship to the current traversing the potential winding, irrespective of the power factor of the circuit; I a

In the accompanying drawing, the single figure is a diagrammatic illustration of the vention. t

An alternating-current electric clrcuit 1 has a meter '2 connected thereto. The meter and isadapted to be'defiected in accordance ..V 1" I -tr1c clrcuit 1. Y The induction regulator 11 is mechan1cally connected to a small alternatmg-currenttorque motor 12, which is con nected in series with the electrimcircuit'l,

with the varying-currents therein;.

'Byxreason ot the. operative connections between the motor 12 and the-regulator 11,

the regulator 11 will bedeflect'ed in accordance with the currentin the electric circuit 1; Hence, the secondary voltage'of the inductlon regulator will be proportional to 'the current .in thecircuit, but, by reason'of the shunt connection of the primarvWindfling to'the circuit, .this voltage will-be in fixed-phase relation to the voltageof the circuit, or at a definite fixed angle thereto. Consequently, the current winding of the meter 2 will be traversed by a current which is, at all times, proportional to the current traversing the electric circuitl at a -fixed phase position with reference to the voltage. Hence, the meter armature will be operated in proportion to thedirect product of the voltage and the current in the electric circuit 1 or in accordance withthe volt amperes. I

I do not wish to be limited to the structure and apparatus hereinsetforth, as nugized in accordance with one of the factors of the-apparent energy of thecircuit, an'lnduction regulator having a primary winding connected to the circuit and a secondary ing, and a torque motor device responsive to only one quantity ofthe circuit for actuating said regulator. j

- 2. A volt-ampere meter for an alternat-' i I ing-current circuit comprising a movable member, windings responsive to two 'fixedphase elements derivedfrom the circuit, one

of said elements being responsive to oneof the factors of the apparent "energy of the circuit, and means for effecting an inducwinding connectedto the other meter wind tively derived current in the other vvinding in accordance Withthe other factor'of the,

apparent energy of" the circuit.

3. A volt-ampere meter for an alternat- 1ng current circuit compris ng a movable 1ndicating member, windings for actuating thesame', one-of said windings being energized in accordance With one of the factors of the apparent energy of the circuit,an inductlon regulator having a-.-pr1mary wlnd for an alternatto the circuitto be energized in accordance :Witlrone of the factors of theapparent energy of thecircuit, of' means for energizmg: the other WlIlCllIIg'Hl accordance-With the other factor of the 'apparent'energy of thecircuit, said'means comprising atorque Jmotor' having series-related stat onary and movable elements connected to the circuit,

and an induction regulatoractuated hy'said motor," said motor comprising a movable element connectedin circuitwith said; other 7 Winding and a stationary element connected to the circuit. j 4 V Q 5; In avolt-a'mpere meter for an alter-nan ing-current circuit, the combination with a movable member and' actuating windings therefor, one ofwhich is connected across the circuit, of means for varying the current of the otherwinding in accordance with the currentof the circuit, said means com prising an induction regulator having aprimary Winding connected'across the circuit and a secondary Winding connected in series:

relation to said other meter Winding,.and a torque motor device for actuating-said regulator, Said motor comprising statlonary and movable windings connectedin series relation to each other and to-said circuit.

In testimony whereof, I have hereunto subscribed my name this 30th day of November 1920/ 1 LEO 130mm; I 

